Disassemble a Metal 80mm EL-Nikkor for Cleaning

[igoriginal]

Here ya go. I put together a very basic photo guide, demonstrating how easy it is to disassemble the older, chrome-base, all-metal El Nikkor 80mm F/5.6, for cleaning.

 

 

1. The front of the lens, with yellow arrows added to indicate the two "turning slots" where a small flat-head screwdriver can be inserted to aid with twisting the front module (containing the first two elements) from the rest of the lens body.

 

 

2. A high-quality, jeweler's flat-head screwdriver, inserted into one of the turning slots.

 

 

3. A side view, labeled with an indicator to show which part of the actual front module can actually be grabbed onto, and then twisted out (counter-clockwise).

 

 

4. Inserting the screwdriver into one of the turning slots, once more; side-view.

 

 

5. The front module (side view), which contains the two-most front elements, twisted out of the lens body (by hand) - after using the jeweler's flat-head screwdriver to give it an initial "budge."

 

 

6. The front module (top view), which contains the two-most front elements, twisted out of the lens body (by hand). Note the label added, indicating the next step, which will require unscrewing the even smaller retaining ring which holds the second-from-the-front element in place. Note also the element now exposed within the body of the lens, right behind the aperture mechanism. This can also be cleaned.

 

 

7. Unscrewing the retaining ring from the rear of the front module, by hand (pliers can be carefully used, if the ring is particularly tight.)

 

 

8. Final step: Retainer ring removed from the rear of the front module. Then, the second-from-the-front element, removed from being stacked against the front-most element. Now, one can effectively clean both sides of three elements (the front, the second, and then the rear element behind the aperture mechanism of the remaining part of the lens body).

 

[colinbm]

Thanks Iggy, for a look into this lens, looks good. Now to do it.

Col

[Andrea B.]

Editor's Note: I have made this a separate topic for easier future reference and searching.

[Johan]

Can I add something - if you find it tough to do step 2, a useful thing to buy on ebay is a £10 "lens repair wrench" "lens spanner". This is a tool that can be adjusted on metal bars and gives two opposing points of force so you can easily twist your retaining ring. When grease solidifies or when they're overtightened by a previous owner they can be tricky to get off.

[igoriginal]

Excellent suggestion, Johan!

 

I had wondered if there was such a thing as such a device, for a more "gentle" grip on the part of the barrel that twists out ... rather than using plyers (which I have marred and even bent the barrels of quite a few lens, including stripping away filter threads. Yikes.)

 

And using a "vice" isn't always viable, either, if the metal is particularly soft, as is the case with some older, aluminum-shelled designs.

 

Thanks for this! Very useful! I think I am going to buy one, now. :D

[JCDowdy]

A safer way:

1. Flip over a mouse pad rubber surface up.

2. Place lens front down against rubber surface.

3. Grip lens firmly and rotate counter clockwise while pressing down against rubber surface.

 

This method actually provides much more leverage and you are much less likely to mar the slots or slip and dig the front element with a metal tool.

If more leverage is needed to unscrew I use a stone drink coaster with a disk of rubber cemented to the bottom for padding.

Be sure no part of the rear element extends out far enough to touch the rubber on the bottom of the coaster.

The diameter of a typical drink coaster is large enough to produce considerably more leverage than simply gripping the lens by hand.

- I used this method to unscrew a very tight 135mm 105mm EL-Nikkor for cleaning, and just now checked an 80mm and 50mm all seem to be amenable to this approach.

[Andrea B.]

There are thin, flexible round rubber (or similar) jar openers which are also useful for this purpose.

[igoriginal]

Yes, all of these "gripping tools" would also be quite viable. All excellent ideas.

 

Of course, there are those less common situations in which an unscrewable part of a lens doesn't have much to "grip" with, or, the barrel is built with a front-element component which is deeply recessed.

 

In these cases, I think Johan's tool suggestion remains the more "professional" choice of proceeding with disassembly.

 

There really is a significantly reduced risk of slippage with said tool, because these "lens turning wrenches", with removable and variable tips (depending on what insert is needed for the job) are designed to specification to lock quite flush with whatever "turning notch" exists on a retaining ring.

 

Here are photos (below) of the one that I just ordered. You can see that the diameter between the two turning forks is adjustable, and lockable. And since this is a "double insertion" tool (utilizing both turning notches on a lens's retaining ring), then there is added stability of a "counter force", as Johan stated.

 

Although, I definitely would resort to the wrench technique last, of course, if the "rubber gripping" ideas would prove to not give way to any success. It's just that some lenses are so badly corroded (or warped, or otherwise) along their threading paths where removable modules couple together, that the hard turn of a dedicated double-pronged lens-turning wrench becomes the only remaining option. Or, in the occasional case where there is really no substantial surface to apply a grip with.

 

These dedicated, adjustable, double-pronged, lens-turning wrenches are quite stable and supply good leverage ... as I am learning just now (and reading up on). Unlike my "single prong" makeshift approach with my jeweler's flat-head ... which does not have a counter-point (opposing prong), and hence, very low stability.

[igoriginal]

But, anyway: I would have to agree though, that it would be prudent to first exhaust all "soft turn" options (applied rubber, fabric, etc., to assist with hand-turning) ... before moving to a "hard turn" approach (dedicated wrench). That would be my logic, anyway.

[Andrea B.]

This ring-notch tool would also be useful for removing the Baader-U retaining ring

in order to flip the pink side out. :D :D :D

[igoriginal]

This ring-notch tool would also be useful for removing the Baader-U retaining ring

in order to flip the pink side out. :D :D :D

 

 

Good call on that, Andrea.

 

Yes, indeed. I have been reading the documentation on the tool, and it states that it was also designed for filter ring setting and / or unlocking, for those who build their own threaded filters from scratch (cutting their own filter glass circles from bulk glass plates, and inserting them into filter-holder blanks, then locking them into place. Or even servicing filter holders / retainers, by unlocking them, and replacing the glass).

[colinbm]

That ring tool is the bees knees Iggy.

Do you have a link to its purchase please ?

I'll write up my experiences with the "N" later :D

Col

[igoriginal]

That ring tool is the bees knees Iggy.

Do you have a link to its purchase please ?

I'll write up my experiences with the "N" later :D

Col

 

Best thing for you to do is simply go to Ebay, and type "lens wrench" into the search box, above. The reason I would rather you do this, instead of give you any specific link ... is because there are so many model variants floating around out there, and in varying countries of shipping origin, as well as projected shipping times. Thus, I feel it's best for someone to do their own comparison, and decide which offering meets their optimal criteria / preferences.

 

In fact, here is my original saved search. It lists 405 results: http://www.ebay.com/...cat=0&_from=R40

[colinbm]

Thanks Iggy

I like that flat bar design one, I think it will twist or wrack less then the others ?

Col

[igoriginal]

Thanks Iggy

I like that flat bar design one, I think it will twist or wrack less then the others ?

Col

 

My thoughts, exactly. The "steel ruler"-like design seems to be more "industrial"-grade ... and thus, less prone to warping and bending. Plus, extra room to get a handful of grip.

 

I have an industrial-grade digital caliper built the same exact way. And that thing can take a beating.

[colinbm]

I have disassembled the newer plastic, EL-Nikkor 80mmF5.6N - M39 Screw Mount, enlarger lens & show here the differences to the older metal EL-Nikkor 80mmF5.6 shown above.

I couldn't open the front element stack with the usual rubber tool. I needed to drill two, 1mm holes in the front ring, in the filter thread recess, so I could open the front element stack.

To stop light leaks into the lens, I turned the back flange 120 degrees, to block the rear window. I 'blacked out', with satin black nail varnish, the white plastic aperture housing, behind the aperture index window.

Cheers

Col

[Johan]

The one I have has two bars across rather than one. Two makes it more stable - not one single point of rotation. But I'm sure one will do fine.

[msubees]

Igor,

Thank you for your help! I was able to open both of my EL 80 yesterday and cleaned all the haze out. I had an easier time after removing the aperture ring (there is a set screw on the side, which was easy to remove), then you have more area to grab for the front element to turn it. one i used my hand, the other I used a pair of pliers with some cloth in between.

[msubees]

I was able to file the tips to be thinner and use this strange tool, as a wrench for the lens. I saved another $25... :)

 

I need to move the center piece away since i was always afraid it might scratch my lens. but it did not.

 

anybody knows what this tool was originally designed for?